1. Field of the Invention
The present invention relates to pupil dilation procedures. More particularly, the present invention relates to a method and apparatus for using electrophoresis to deliver pupil dilation and constriction agents.
2. General Background of the Invention
Every individual should have at least one dilated eye examination in adulthood. Many individuals with various eye problems such as macular degeneration, diabetes, threat of detached retina or history of detached retina as well as many other conditions require repeated dilated eye examinations. Dilated eye examinations typically require patients to wait several minutes after application of a dilator drug before the eye is sufficiently dilated for a dilated eye examination to occur.
Electrophoresis is an electrochemical process in which colloidal particles or molecules with a net electric charge migrate in a solution under the influence of an electric current. It is also sometimes called iontophoresis or cataphoresis. Electrophoresis is sometimes used now by others to deliver vitamins (such as Vitamin C) efficiently.
The following patents are incorporated herein by reference:
______________________________________ U.S. Pat. Nos.: 5,498,521 5,192,665 5,522,864 5,174,304 2,525,381; ______________________________________ EP325,201; Fr.641,745; Germ. 1489708.
U.S. Pat. No. 2,525,381 discloses a contact lens type electrode holder. This electrode holder is used during ionic medication treatment of a patient's eye. The electrode itself has a relatively small surface area. The patent mentions "penicillin or other medicaments".
U.S. Pat. Nos. 5,174,304 and 5,222,864, Fr. Pat. No. 641,745, Germ. Pat. No. 1,489,708, and EP Pat. Office Publication No. 325,201 disclose electrodes for contacting eyeballs.
U.S. Pat. No. 5,498,521 discloses the use of a contact lens electrode placed on a topically anesthetized cornea after dilation of the pupils (see column 17, lines 13-16).
Also incorporated by reference are the following references:
Sarraf, David, et al., "The role of iontophoresis in ocular drug delivery", Journal of Ocular Pharmacology, vol. 10, no. 1: 69-81 (1994);
Pirch, James H., et al., "A role for acetylcholine in conditioning-related responses of rat frontal cortex neurons: microintophoretic evidence", Brain Research, 586 (1992) 19-26;
Behar-Cohen, Francine F., et al., "Iontophoresis of Dexamethasone in the Treatment of Endotoxin-Induced-Uveitis in Rats", Exp. Eve Res., (1997) 65, 533-545;
Yoshizumi, Marc O., et al., "Determination of Ocular Toxicity in Multiple Applications of Foscarnet Iontophoresis", Journal of Ocular Pharmacology and Therapeutics, (1997), 13:6, pp.529-536;
Bradshaw, C. M., et al., "A Procedure for Comparing the Mobilities of Unlabeled Drugs Used in Microelectrophoresis Experiments", Journal of Pharmacological Methods, 5, 67-73 (1981);
McBrien, Neville A., et al., "Experimental Myopia in a Diurnal Mammal (Sciurus Carolinensis) With No Accommodative Ability", Journal of Physiology, (1993), 469, pp. 427-441.